Effect of Paste Volume on Performance of Controlled Low Strength Materials

Controlled low strength material (CLSM) is gaining increasing importance with the growing emphasis on sustainability in construction industry. CLSM can be a valuable application for the safe and efficient use of nonstandard materials such as industrial by-products, which are normally rejected for conventional concrete due to the negative impact on hardened properties. In the present study, a laboratory experiment was carried out to explore the effect of paste volume on flowability and strength development of CLSM. The experimental results showed that the paste volume had a more significant effect on the slump flow compared to the water-cementitious material ratio (w/cm); however, it had little effect on compressive strength of CLSM mixtures. It is proposed that the paste volume percentage can be used to target a desired flow in proportioning of CLSM without compromising the compressive strength of the mixtures.